For the record

• We did not get to the root of the matter when we talked about failure “to route out disease agents” (5 June, p 6).

• We should have been more explicit&colon; atomic clocks rely on the frequency of the electromagnetic radiation that is absorbed or emitted as electrons make transitions between different energy states, not how frequently these transitions occur (5 June, p 8).

• The fish eggs mentioned by Andy Bebington would not have belonged to …